;
; Copyright (c) 2012 Johann Hanne
;
; Permission is hereby granted, free of charge, to any person obtaining a copy
; of this software and associated documentation files (the "Software"), to deal
; in the Software without restriction, including without limitation the rights
; to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
; copies of the Software, and to permit persons to whom the Software is
; furnished to do so, subject to the following conditions:
;
; The above copyright notice and this permission notice shall be included in
; all copies or substantial portions of the Software.
;
; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
; IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
; FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
; AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
; LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
; OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
; THE SOFTWARE.
;

.186
.model large

extrn __bss_start:far
extrn __bss_end:far

extrn __heapinit_:far
extrn main_:far

.code

start:
    cli
    cld

    ; init stack segment and stack pointer
    mov    ax,0x3f00
    mov    ss,ax
    mov    sp,0xfffe

    ; note that we don't need to copy the data segment; the bootstrap
    ; copied the complete flash to RAM, so all data is already writeable

    ; init bss segment
    mov    ax,seg __bss_start
    mov    ds,ax
    mov    es,ax
    xor    ax,ax
    mov    di,offset __bss_start
    mov    cx,offset __bss_end
    sub    cx,di
    shr    cx,1
    ; if there is no bss, there is nothing todo...
    jcxz   skip_init_bss
    rep stosw
skip_init_bss:

ifndef NO_HEAP
    call  __heapinit_
endif

    call  main_

end start
